JP3965173B2 - X-ray fluorescence analyzer and program used therefor - Google Patents

Description

  The present invention relates to a fluorescent X-ray analyzer that analyzes the composition and area density of a sample by the FP method and a program used therefor.

  Conventionally, there is an X-ray fluorescence analyzer that analyzes a composition and an area density of a sample using a fundamental parameter method (hereinafter referred to as FP method). In the FP method, the theoretical intensity of secondary X-rays generated from each element in a sample is calculated based on the assumed element concentration, and the theoretical intensity and the measured intensity measured by the detection means are converted into a theoretical intensity scale. The concentration of the element in the sample is calculated by successively correcting the assumed element concentration so that the converted measurement intensity matches. Here, elements that do not measure fluorescent X-rays, such as oxygen and carbon (elements that cannot measure fluorescent X-rays due to their small intensity and large attenuation due to absorption, hereinafter referred to as non-measuring elements) are usually used as the remainder Although handled, samples that contain many non-measuring elements and whose atomic numbers cannot be specified, such as sludge, incinerated ash, and biological samples, are problematic. Related to this, there are the following conventional techniques.

  In the technique described in Patent Document 1, as an example, in a sample that is known to be composed only of carbon, oxygen, and hydrogen, carbon and oxygen correspond to the intensity of each fluorescent X-ray as a measurement element, and only hydrogen is used. As a non-measuring element, the intensity ratio of Compton scattered rays and Thomson (Rayleigh) scattered rays is made to correspond to the fluorescent X-ray intensity.

  In the technique described in Non-Patent Document 1, the average atomic number of the entire sample is obtained based on the intensity ratio between Compton scattered rays and Thomson scattered rays, and the weight of the sample is obtained.

In the technique described in Non-Patent Document 2, an average atomic number is assumed for non-measurement elements, and scattered radiation is used as the corresponding secondary X-ray.
JP 2001-255289 A P. Van Espen et.al, Effective Sample Weight from Scatter Peaks in Energy-Dispersive X-Ray Fluorescence, “ANALYTICAL CHEMISTRY”, (USA), 1979, VOL.51, NO.7, p.961-967 KK Nielson et.al, COMPARISON OF X-RAY BACKSCATTER PARAMETERS FOR COMPLETE SAMPLE MATRIX DEFINITION, “Advances in X-ray Analysis”, (USA), 1984, Vol.27, p.449-457

  However, as in the technique described in Patent Document 1, oxygen and carbon can be measured only for a sample that can be analyzed in a vacuum or without a sample protective film, and a powder sample using a liquid sample or a sample protective film. Then, since oxygen and carbon are non-measuring elements, they cannot be analyzed. In addition, the technique disclosed in Patent Document 1 is limited to a sample in which an element handled as a non-measurement element is known, and a sample in which the non-measurement element cannot be specified cannot be analyzed. In the technique described in Non-Patent Document 1, since the average atomic number of the entire sample is used, an accurate mass absorption coefficient cannot be obtained for an element having an atomic number smaller than the average atomic number. Can not. In the technique described in Non-Patent Document 2, it is understood that the average atomic number of the non-measurement element is obtained from the scattering cross section, but since the intensity ratio of Compton scattered radiation / Thomson scattered radiation cannot be used, hydrogen, carbon, It cannot be applied to samples such as polymers and liquids mainly composed of oxygen, and can only be applied to samples such as rocks where the concentration of non-measuring elements is low. In other words, any of the conventional techniques cannot sufficiently analyze various samples that contain many non-measurement elements and whose atomic numbers cannot be specified.

  The present invention has been made in view of the above-mentioned conventional problems, and in a fluorescent X-ray analyzer that analyzes the composition and area density of a sample by the FP method and a program used therefor, it contains a large number of non-measuring elements and identifies the atomic number. An object of the present invention is to provide a sample that can be analyzed sufficiently accurately for various samples that cannot be obtained.

In order to achieve the above object, the first configuration of the present invention includes an X-ray source that irradiates a sample with primary X-rays, fluorescent X-rays generated from each element in the sample, and scattered light of primary X-rays . Based on the detection means for measuring the intensity and the assumed concentration of the element, the theoretical intensity of fluorescent X-rays generated from each element in the sample is calculated, and the theoretical intensity and the measured intensity measured by the detection means are calculated as the theoretical intensity. In a fluorescent X-ray analysis apparatus comprising: a calculation means for calculating the concentration of an element in a sample by sequentially correcting and correcting the assumed element concentration so that the converted measurement intensity converted into a scale matches. The non-measurement element that does not measure the fluorescent X-ray is assumed to have an average atomic number, and the scattered light is used in correspondence with the scattered radiation instead of the fluorescent X-ray. Created for each X-ray and each scattered ray By solving the partial simultaneous equations, by obtaining the correction values to update the average atomic number correction value and said assumed for updating the density of the assumed elements, the theoretical strength with the conversion measured intensity and are consistent As described above, the concentration of the element in the sample is calculated by correcting the assumed concentration of the assumed element and the assumed average atomic number in an approximate manner.

According to the apparatus of the first configuration, the average atomic number of the assumed non-measuring element is also successively approximated so that the theoretical intensity of the fluorescent X-ray and the converted measured intensity coincide with each other, similarly to the assumed element concentration. Since there are many types of correction calculations that can be selected as the theoretical intensity and measurement intensity of the scattered radiation, it is possible to analyze sufficiently accurately various samples that contain many non-measurement elements and whose atomic numbers cannot be specified.

  The theoretical intensity and measured intensity of the scattered radiation include the theoretical intensity and measured intensity of the primary X-ray continuous X-ray scattered radiation, the theoretical intensity and measured intensity of Compton scattered radiation, the theoretical intensity and measured intensity of Thomson scattered radiation, In addition, one selected from the group consisting of the theoretical intensity ratio and the measured intensity ratio of any two of the scattered rays can be used.

  In the apparatus of the first configuration, the calculation means calculates the theory of the scattered radiation based on the overlap between the Thomson scattered radiation and the fluorescent X-ray and / or the relative measurement accuracy estimated from the measured intensity and measurement time of the Thomson scattered radiation. It is preferable to select one from the group as the intensity and the measured intensity. According to this preferable configuration, the scattered radiation to be measured is appropriately automatically selected.

  Moreover, in the apparatus of 1st structure, the said calculation means is an apparatus sensitivity for converting the measured intensity ratio of a Compton scattered ray and a Thomson scattered ray and the measured intensity of the said scattered ray into a theoretical intensity scale beforehand for every kind of sample. It is preferable to determine the type of the sample based on the measured intensity ratio between the Compton scattered ray and the Thomson scattered ray, and obtain the converted measured intensity using the corresponding device sensitivity. According to this preferable configuration, the apparatus sensitivity is appropriately automatically set according to the type of the sample.

Furthermore, in the apparatus of the first configuration, the calculation means assumes an average atomic number for elements other than hydrogen among the non-measurement elements, and instead of fluorescent X-rays, Compton scattered radiation, Thomson scattering Any one of the scattered X-rays and the continuous X-rays of the primary X-ray is used correspondingly, and for hydrogen, assuming the concentration thereof , the average atomic number is used instead of the fluorescent X-ray. It can have use in association with different scattered radiation from the scattered radiation corresponding to elements other than hydrogen assuming. According to this configuration, since the non-measuring element is divided into hydrogen and other elements, the sample that is a polymer or liquid containing a large amount of hydrogen can be analyzed more accurately.

The second configuration of the present invention is based on an X-ray source that irradiates a sample with primary X-rays, detection means that measures the intensity of fluorescent X-rays generated from each element in the sample, and the assumed element concentration. The theoretical intensity of fluorescent X-rays generated from each element in the sample is calculated, and the assumption is made so that the theoretical intensity matches the measured intensity measured by the detecting means and converted to the theoretical intensity scale. In a fluorescent X-ray analysis apparatus comprising a calculating means for calculating the concentration of an element in a sample by successively approximating and calculating the concentration of the element, a non-measurement element for which the calculating means does not measure fluorescent X-rays. , assuming the average atomic number, used in association with X-ray fluorescence of elements constituting the substrate a fluorescent X-ray or a sample of a predetermined amount of addition of these elements is adhered to the specimen, the intensity at the detector Created for each measured fluorescent X-ray By solving the partial simultaneous equations, by obtaining the correction values to update the average atomic number correction value and said assumed for updating the density of the assumed elements, the theoretical strength with the conversion measured intensity and are consistent As described above, the concentration of the element in the sample is calculated by correcting the assumed concentration of the assumed element and the assumed average atomic number in an approximate manner.

  That is, in the apparatus of the first configuration, the scattered radiation is associated with the non-measurement element, whereas in the apparatus of the second configuration, the fluorescent X-ray of the internal standard element is associated. The same effects as the first configuration apparatus can be obtained by the second configuration apparatus.

  A third configuration of the present invention is a program for causing a computer included in the device having the first or second configuration to function as the calculation unit. The same effect as the apparatus of the first configuration can be obtained by the program of the third configuration of the present invention.

  The X-ray fluorescence analyzer according to the first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, this apparatus includes a sample stage 8 on which a sample 13 is placed, an X-ray source 1 that irradiates the sample 13 with primary X-rays 2, and fluorescent X-rays and scattering generated from the sample 13. And a detecting means 9 for measuring the intensity of the secondary X-ray 4 such as a line. The detection means 9 includes a spectroscopic element 5 that splits secondary X-rays 4 generated from the sample 13 and a detector 7 that measures the intensity of each of the split secondary X-rays 6. In addition, it is good also as a detection means not using the spectroscopic element 5, but a detector with high energy resolution.

  Then, based on the assumed element concentration, the theoretical intensity of the secondary X-ray 4 generated from each element in the sample 13 is calculated, and the theoretical intensity and the measured intensity measured by the detecting means 9 are converted into a theoretical intensity scale. The calculated element 10 includes a calculating means 10 for calculating the concentration of the element in the sample 13 by successively correcting the assumed element concentration so as to match the calculated measured intensity. For non-measurement elements that do not measure 4, use the scattered radiation 4 as the corresponding secondary X-ray, assuming the average atomic number, and change the assumed average atomic number so that the theoretical intensity and the converted measured intensity match. Corrective calculation is performed in successive approximation.

  The theoretical intensity and measured intensity of the scattered radiation include the theoretical intensity and measured intensity of the primary X-ray continuous X-ray scattered radiation, the theoretical intensity and measured intensity of Compton scattered radiation, the theoretical intensity and measured intensity of Thomson scattered radiation, In addition, one selected from the group consisting of the theoretical intensity ratio and the measured intensity ratio of any two of the scattered rays can be used.

  This device operates as follows. The sample 13 placed on the sample stage 8 is irradiated with the primary X-ray 2 from the X-ray source 1, and the generated secondary X-ray 4 is incident on the spectroscopic element 5, and the dispersed secondary X-ray 6 is obtained. The intensity is measured by the detector 7 every time. And the calculation means 10 performs a calculation according to the flowchart shown in FIG.

  First, in step 1, the initial value of the concentration of each measurement element, the initial value of the average atomic number of the non-measurement element, and the initial value of the area density (or thickness) of the sample are set as necessary. Although the initial value of the concentration of each measurement element can be set according to the type of the sample, all may be set to 1 mass%. The initial value of the average atomic number of the non-measurement element is set to 8, for example.

Next, in step 2, the measured intensity I _measM of the fluorescent X-rays and scattered rays is converted into a theoretical intensity scale by the following formula (1) to obtain respective converted measured intensity I _measT .

I _measT = A (I _measM ) ² + BI _measM + C (1)

Next, in Step 3, based on the initial value set and calculates the theoretical intensity I _STi of theoretical strength I _FTi and scattered radiation of each X-ray fluorescence. A known formula is used.

Next, in step 4, the concentration of each measurement element and the average atomic number of the non-measurement element are changed by predetermined values, and the changed theoretical intensity is calculated. In other words, for fluorescent X-rays, the theoretical intensity of i element when the concentration of the j element is changed by dw% and the theoretical intensity of the i element _IFTI ^j and the average atomic number of the non-measurement element are changed by dZ. For the intensity I _FTi ^Z , the scattered radiation, the theoretical intensity I _STi ^j of the i scattered radiation when the concentration of the j element is changed by dw%, and i when the average atomic number of the non-measurement element is changed by dZ Calculate the theoretical intensity I _STi ^Z of the scattered radiation. For example, dZ is set to 0.05.

  Next, in step 5, based on the difference equation, the concentration of each measurement element and the average atomic number of the non-measurement element are updated. Specifically, first, by creating and solving the differential simultaneous equations of the following formulas (2) and (3) for each fluorescent X-ray and each scattered ray, the concentration of each measurement element, the average atom of the non-measurement element Correction values Δwj and ΔZ for updating the number are obtained.

I _fmeasTi −I _FTi = (dI _FTi / dZ) ΔZ + Σ (dI _FTi / dwj) Δwj (2)

I _smearTi −I _STi = (dI _STi / dZ) ΔZ + Σ (dI _STi / dwj) Δwj (3)

  Here, for fluorescent X-rays, each differential term is obtained by the following equation (4).

(dI _FTi / dwj) = ((I _FTi −I _FTi ^j ) / dwj) (4)

  As for the scattered radiation, when the intensity of the scattered radiation such as Compton scattered radiation or Thomson scattered radiation is used alone, each differential term is obtained by the following equation (5) as in the case of fluorescent X-rays.

(dI _STi / dwj) = ((I _STi −I _STi ^j ) / dwj) (5)

As the intensity of scattered radiation, for example, when using the intensity ratio of Compton scattered radiation and Thomson scattered radiation, the intensity ratio of both scattered radiation is applied where the intensity of a single scattered radiation is used. For example, Equation (3), at the theoretical strength _{I STi} of scattered radiation (5), the following equation (6), and a theoretical intensity ratio _{I STIR} scattered radiation, Thomson scatter theoretical strength _{I STiThom} The ratio of the theoretical intensity I _STiComp of the Compton scattered radiation to is applied.

I _STiR = (I _STiComp / I _STiThom ) (6)

Similarly, even before type measuring intensity _{I MeasM} of scattered radiation conversion measured intensities of scattered radiation _{(3) I} smeasMi and Equation (1), also in step 6 to be described later, to apply the intensity ratio of scattered radiation .

The differential simultaneous equations of the equations (2) and (3) created in this way are solved, and the corrected values Δwj and ΔZ are obtained for the concentration wi of each measurement element and the average atomic number Z of the non-measurement element, and the following equation (7) , as shown in (8), the original value _{w Iold,} by adding the _{Z old,} updated value _{w inew,} seek _{Z new new.} The concentration of the non-measurement element is obtained by subtracting the total of the concentration wi of the measurement element from 100%.

wi _new = wi _old + Δwj (7)

Z _new = Z _old + ΔZ (8)

Next, in step 6, based on the average atomic number _{Z new new} concentrations _{wi new new} and unmeasured elements of each measurement element updating, to calculate the theoretical intensity _{I STi} of theoretical strength _{I FTi} and scattered radiation of each X-ray fluorescence The convergence determination is performed based on whether or not the difference from each converted measurement intensity I _measT obtained by the previous equation (1) is equal to or less than a predetermined value. The convergence determination may be performed based on whether or not the difference between the theoretical intensity and the converted measured intensity is equal to or less than a predetermined ratio (for example, 0.1%) of the converted measured intensity. If it is determined that it has not converged, the process returns to step 4 and the steps up to step 6 are repeated until convergence. That is, for the secondary X-rays generated from the sample (fluorescent X-ray of the measurement element and scattered radiation corresponding to the non-measurement element), the assumed concentration of the measurement element is assumed so that the theoretical intensity and the converted measurement intensity match. The average atomic number of the non-measured element is corrected and calculated sequentially.

  Then, if it is determined that it has converged, the process proceeds to step 7 and results in the latest concentration of each measurement element, the average atomic number of the non-measurement element, and the area density (or thickness) of the sample as necessary. Output.

  The step 5 can be executed separately in the following steps 5A and 5B. First, in step 5A, the average atomic number of the non-measurement element is fixed, and only the concentration of each measurement element is updated. Next, in step 5B, the concentration of each measurement element is fixed to the latest value, ΔZ is obtained from the following equation (9), and only the average atomic number of the non-measurement element is updated.

I _smearTi −I _STi = (dI _STi / dZ) ΔZ (9)

  In addition, when analyzing the area density at the same time, one scattered ray to be measured is added, the previous equation (3) is added to the scattered ray, and the right side of each equation (2) and (3) of the differential simultaneous equations What is necessary is just to add the area density differential term to. For example, the previous equation (3) becomes two equations, an equation for Compton scattered rays and an equation for Thomson scattered rays.

Next, the intensity of the scattered radiation used will be described in more detail. First, when an element having an atomic number from 1 to 9 (hydrogen to fluorine) is used as a sample, and the area density is assumed to be 4 types in the range of 100 to 99999 mg / cm ² , and an Rh tube is used as an X-ray source. Theoretical calculation of the intensity of the Rh-Kα Compton scattered ray generated from the sample, the intensity of the Rh-Kα Thomson scattered ray, and the ratio of the Rh-Kα Compton scattered ray to the Rh-Kα Thomson scattered ray intensity The results obtained are shown in FIGS. According to this, the intensity of Compton scattered radiation is strongly influenced by the area density on the side where the atomic number is small and Thomson scattered radiation is on the side where the atomic number is large, whereas the intensity ratio between Compton scattered radiation and Thomson scattered radiation is It can be seen that there is a monotonic decrease with respect to the atomic number, with little influence from the area density.

  Therefore, it is appropriate to use the intensity ratio between Compton scattered radiation and Thomson scattered radiation for a sample or the like whose area density cannot be measured accurately. In addition, when a Compton scattered ray or a Thomson scattered ray is made to correspond to the whole non-measurement element in a polymer or liquid sample mainly containing hydrogen, carbon, oxygen, etc., the theoretical intensity and An average atomic number that matches the converted measurement intensity cannot be obtained, and an accurate analysis result cannot be obtained. It is also appropriate to use the intensity ratio of Compton scattered light and Thomson scattered light for such a sample. On the other hand, when the Thomson scattered ray overlaps with the fluorescent X-ray or the intensity is small and measurement is difficult, only the intensity of the Compton scattered ray is used.

  It is also possible to divide non-measuring elements into other than hydrogen and hydrogen, assume an average atomic number for non-measuring elements other than hydrogen, and use both Compton scattered light intensity and Thomson scattered light intensity. That is, the previous formula (3) becomes two formulas for the Compton scattered ray and the Thomson scattered ray, and the differential of the hydrogen concentration on the right side of the differential simultaneous equations (2) and (3). Add a term.

  In this case, the calculation means assumes the average atomic number for the elements other than hydrogen among the non-measurement elements, uses the first scattered radiation (for example, Compton scattered radiation) as the corresponding secondary X-ray, Assuming the concentration, using the second scattered radiation (for example, Thomson scattered radiation) as the corresponding secondary X-ray, the assumed average atom so that the theoretical intensity and the converted measured intensity coincide with each other The number and hypothesized hydrogen concentration are calculated by successive approximation. According to this configuration, since the non-measuring element is divided into hydrogen and other elements, the sample that is a polymer or liquid containing a large amount of hydrogen can be analyzed more accurately.

  In the above, instead of Compton scattered radiation, scattered radiation (background) of primary X-ray continuous X-rays can also be used.

  As described above, the theoretical intensity and measured intensity of scattered radiation include the theoretical intensity and measured intensity of primary X-ray continuous X-ray scattered radiation, the theoretical intensity and measured intensity of Compton scattered radiation, the theoretical intensity of Thomson scattered radiation and The measurement intensity and a group consisting of the theoretical intensity ratio and the measurement intensity ratio of any two of the scattered radiation can be selected from the group consisting of Thomson as follows. It may be automatically performed based on the overlap between the scattered radiation and the fluorescent X-ray and / or the relative measurement accuracy estimated from the measurement intensity and measurement time of the Thomson scattered radiation.

The overlap of Thomson scattered radiation and X-ray fluorescence, for example, it utilizes a Thomson scattered radiation Rh -Keiarufa line when using Rh tube to the X-ray source, Mo -Kβ ₂ lines and U-Lr as near line Since there are fluorescent X-rays such as _two lines, Mo or U is detected, and the intensity at which the adjacent line overlaps the Rh-Kα line is greater than or equal to a predetermined ratio (for example, 2%) with respect to the intensity of the Rh-Kα line. Sometimes, it is determined that there is an overlap, and the theoretical intensity and measured intensity of Compton scattered rays of Rh-Kα rays are selected as the theoretical intensity and measured intensity of scattered rays. Even when the sample Rh of the tube target element is included in the sample, the determination is made in the same manner as when the above-described Mo or U is included in the sample. To detect the tube target element Rh, a primary filter is used, and the characteristic X-ray (Rh-Kα ray in this example) of the tube target element of the primary X-ray is cut and measured. Further, in calculating the net intensity of the Thomson scattered radiation, not only the peak of the Rh-Kα ray but also the background position is measured, and the overlap of fluorescent X-rays is similarly determined for the background position.

  Regarding the relative measurement accuracy of Thomson scattered radiation, for example, when the relative measurement accuracy is below a predetermined value, select the theoretical intensity ratio and measured intensity ratio of Compton scattered radiation and Thomson scattered radiation as the theoretical intensity and measured intensity of the scattered radiation. When the value is larger than the predetermined value, the theoretical intensity and measured intensity of the Compton scattered radiation are selected. In particular, in the case of a small sample or a sample containing a heavy element as a main component, the intensity of Thomson scattered radiation is reduced, and the relative measurement accuracy is lowered. Also, the relative measurement accuracy decreases when the measurement time is shortened. The predetermined value as the determination criterion is determined by the degree of influence of the measurement intensity error of the Thomson scattered radiation on the analysis value, and is 2%, for example.

  Moreover, even if the scattered radiation used is the same, the sensitivity of the apparatus for converting the measured intensity of the scattered radiation into the theoretical intensity scale differs somewhat depending on the type of sample, such as whether it is a polymer or an oxide powder. Therefore, the calculation means stores in advance the measurement intensity ratio of the Compton scattered ray and the Thomson scattered ray and the device sensitivity for each type of sample, and the type of sample based on the measured intensity ratio of the Compton scattered ray and the Thomson scattered ray. Can be determined automatically, and the corresponding measured sensitivity can be used to appropriately determine the converted measured intensity. That is, the apparatus sensitivity can be automatically set appropriately according to the type of sample.

  Table 1 compares the results of analyzing the sample that is incinerated ash with the apparatus of the first embodiment described above with the results of analyzing the remainder as oxygen with the apparatus using the conventional FP method and the standard values. Shown in

  According to this, among the 11 measurement elements, only in Ni, the analysis value by the apparatus of the first embodiment is slightly far from the standard value than the analysis value by the conventional apparatus, but in Sb, the remaining 9 are the same. The analysis value by the apparatus of the first embodiment is closer to the standard value than the analysis value by the conventional apparatus, and the apparatus of the first embodiment is more accurate for the entire analysis. That is, according to the apparatus of the first embodiment, it is possible to analyze a sample that contains a large amount of non-measuring elements and whose atomic number cannot be specified sufficiently accurately.

  Next, a fluorescent X-ray analyzer according to the second embodiment of the present invention will be described. As secondary X-rays corresponding to non-measuring elements, scattered light is used in the apparatus of the first embodiment. In the apparatus of the second embodiment, fluorescent X-rays of internal standard elements, specifically, samples are used. The only difference is that a fluorescent X-ray of an element added in a predetermined amount or a fluorescent X-ray of an element constituting the substrate to which the sample is attached is used. That is, instead of increasing the previous formula (2) by one, the previous formulas (3), (5), and (6) become unnecessary. Further, the following formula (10) is used instead of the previous formula (9).

I _fmeasTi −I _FTi = (dI _FTi / dZ) ΔZ (10)

  According to the apparatus of the second embodiment, even when the Compton scattered radiation cannot be measured using an X-ray tube or the like of a Cr target as an X-ray source, the same effect as the apparatus of the first embodiment can be obtained. .

  The apparatuses of the first and second embodiments described above normally include a computer, but a program for causing the computer to function as the calculation unit is also an embodiment of the present invention.

It is the schematic which shows the fluorescent X-ray-analysis apparatus of 1st, 2nd embodiment of this invention. It is a flowchart which shows operation | movement of the calculation means with which the apparatus is provided. It is a figure which shows the result of having theoretically calculated the relationship between the atomic number of the sample which consists of a single light element, and the intensity | strength of the Compton scattered ray of Rh-K (alpha) generated from a sample about four types of area densities. Similarly, it is a figure which shows the relationship between the atomic number of a sample, and the intensity | strength of the Rh-K (alpha) Thomson scattered ray generate | occur | produced from a sample. Similarly, it is a figure which shows the relationship between the atomic number of a sample, and the ratio of the intensity | strength of the Rh-Kα Compton scattered ray to the intensity of the Rh-Kα Thomson scattered ray generated from the sample.

Explanation of symbols

1 X-ray source 2 Primary X-ray 4 Secondary X-ray (fluorescent X-ray, scattered radiation)
9 Detection means 10 Calculation means 13 Sample

Claims (7)

An X-ray source for irradiating the sample with primary X-rays;
Detection means for measuring the intensity of fluorescent X-rays and primary X-ray scattered rays generated from each element in the sample ;
Based on the assumed element concentration, the theoretical intensity of fluorescent X-rays generated from each element in the sample is calculated, and the converted intensity measured by converting the theoretical intensity and the measured intensity measured by the detection means into a theoretical intensity scale; In the fluorescent X-ray analysis apparatus comprising the calculating means for calculating the concentration of the element in the sample by sequentially correcting and correcting the assumed element concentration so as to match,
For the non-measuring element that does not measure the fluorescent X-ray, the calculation means assumes an average atomic number, uses the scattered radiation instead of the fluorescent X-ray, and uses the detection means to measure the intensity of the fluorescent X By solving the differential simultaneous equations created for each line and each scattered ray, obtaining a correction value for updating the assumed element concentration and a correction value for updating the assumed average atomic number, the theory Fluorescence characterized in that the concentration of the assumed element and the assumed average atomic number are successively approximated and corrected so that the intensity and the converted measured intensity coincide with each other to calculate the concentration of the element in the sample X-ray analyzer. In claim 1,
The theoretical intensity and measured intensity of the scattered X-ray, the theoretical intensity and measured intensity of the primary X-ray continuous X-ray, the theoretical intensity and measured intensity of the Compton scattered ray, the theoretical intensity and measured intensity of the Thomson scattered ray, and A fluorescent X-ray analyzer using one selected from the group consisting of the theoretical intensity ratio and the measured intensity ratio of any two of the scattered rays. In claim 2,
Based on the relative measurement accuracy estimated from the overlap between Thomson scattered rays and fluorescent X-rays and / or the measured intensity of Thomson scattered rays and the measurement time, the calculation means uses the group as the theoretical intensity and measured intensity of the scattered rays. X-ray fluorescence analyzer for selecting one from the following. In any one of Claims 1 thru | or 3,
The calculation means stores in advance the measurement intensity ratio of Compton scattered radiation and Thomson scattered radiation for each type of sample and device sensitivity for converting the measured intensity of the scattered radiation into a theoretical intensity scale, and Compton scattered radiation And a Thomson scattered radiation measurement intensity ratio, a fluorescent X-ray analyzer that determines the type of sample and obtains the converted measurement intensity using the corresponding apparatus sensitivity. In claim 1,
For the elements other than hydrogen among the non-measured elements, the calculating means assumes a mean atomic number, and instead of fluorescent X-rays, Compton scattered rays, Thomson scattered rays and primary X-ray continuous X-rays Any one of the scattered rays is used correspondingly, and with respect to hydrogen, assuming its concentration, it corresponds to an element other than hydrogen assuming the average atomic number instead of fluorescent X-ray. scattered ray fluorescence X-ray analysis apparatus are use in association with different scattered radiation from. An X-ray source for irradiating the sample with primary X-rays;
Detection means for measuring the intensity of fluorescent X-rays generated from each element in the sample ;
Based on the assumed element concentration, the theoretical intensity of fluorescent X-rays generated from each element in the sample is calculated, and the converted intensity measured by converting the theoretical intensity and the measured intensity measured by the detection means into a theoretical intensity scale; In the fluorescent X-ray analysis apparatus comprising: a calculation means for calculating the concentration of the element in the sample by sequentially correcting and correcting the assumed element concentration so as to match,
The calculating means, for the unmeasured element which does not measure the fluorescent X-ray, the average atomic number assuming, of elements X-ray fluorescence or sample a predetermined amount the elements added to the specimen constitutes the substrate adhering A correction value for updating the assumed concentration of the element and the assumed average atom by solving the differential simultaneous equations created for each fluorescent X-ray whose intensity is measured by the detection means using the corresponding X-ray fluorescence By calculating a correction value for updating the number, the concentration of the assumed element and the assumed average atomic number are sequentially corrected and calculated so that the theoretical intensity and the converted measurement intensity coincide with each other. An X-ray fluorescence analyzer characterized by calculating the concentration of an element in a sample .   The program for functioning the computer with which the fluorescent X-ray-analysis apparatus as described in any one of Claims 1 thru | or 6 is provided as the said calculation means.

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